Noteable Steamers

[timz]

"Why couldn't the drivers support a wider firebox by extending outward the connecting rods between the driving axle in front of the firebox and the driving axle behind the firebox? That way you have more weight being supported by the drivers (e.g. more traction) instead of a non-driving trailing truck, while still maintaining the advantage of the larger firebox."

Hmm... you're proposing the rear driver would be 20 or 30 feet behind the driver ahead of it, with 20-30-ft side rods? And a firebox that's less than 4 ft wide, and 20-30 feet long?

Or is your firebox to be above the drivers, not between them? If it's above the drivers, why are the siderods a problem?

[M636C]

Another class of GN locomotive with the wide firebox over the driving wheels was the 2-6-8-0 class M-1, 22 of which between 1929 and 1931 were rebuilt to class O-7 Mikados retaining the original boiler. This may be the only example where a given boiler was used both over coupled wheels and later over a trailing truck. The O-7 was of course a very large Mikado with 69" driving wheels. In fact, the O-7s were later rebuilt as O-8 locomotives.

M636C

[GN-Rick]

The GN's Class N locomotives were always 2-8-8-0s. When originally
built in 1912, they were compound locomotives and were equipped
with very small tenders. They were classed N1 at that time. In the years
between 1924 and 1927, the GN took the entire class in hand and rebuilt
them to simple configuration. They added large Vanderbilt tenders at
that time as well and also upgraded appliances like feedwater heaters
and more modern air pumps.This incarnation was classed N2. In 1939,
GN totally rebuilt the entire class again, this time applying new cast
frames, roller bearings, new boilers and modern appliances. This
final form of GN's 2-8-8-0s were classed N3. In this final form, they
were capable of fast freight service and were even occasionally used
on troop trains during WWII. They exerted a tractive effort of 125,000
lbs, according to Robert LeMassena's book, "Articulated Locomotives
of North America". This is an excellent example of a railroad not
giving up on a design, but reworking it until it became a superlative
locomotive. They are not as well known as, for example, GN's other
exceptional loco designs-the O8 Mikado (largest 2-8-2 ever built) and
the R2 2-8-8-2. This may be because the N fleet mostly operated on
the Mesabi Range in iron ore service. When in general freight service,
they could outwork many more-modern designs-NP's Z6 through Z8
Challengers, for example. Hopefully, this is helpful to you.

[Murphy Siding]

Rick: You mentioned that the N-3's were re-built. What were they before?

[GN-Rick]

No problem, Murphy. I was just trying to avoid any confusion. Certainly
not trying to find fault or anything. Have a great day.

[Murphy Siding]

QUOTE: Originally posted by GN-Rick

In fact, that's true, Murphy. The N3 turned out to be the tallest locomotive
on the GN, in part due to that very thing. Actually, I wasn't really advocating
the N3 as a response to futuremodal, I was simply submitting that loco
as a notable achievement by GN's shop forces. The two paragraphs don't
really dovetail that way. I was just expressing the opinion that longer-extended
rods would create a bad counterbalance problem and then a separate
opinion on the N3. It is intersting to note that GN got as much out of
the N3 as it did with that arrangement-of firebox built on top of the rear
drivers instead of a deep, truck-supported firebox as on most modern
steam locomotives of that time.

Rick: I was the one who put the subjects together-'was thinking about futuremodal's question, and suddenly saw a mental picture when I read your post. I e-mailed futuremodal my address, so I'm looking forward to a drawing.

[CSSHEGEWISCH]

The rods were quartered on opposite sides of any steam locomotive to avoid the possibility of both pistons being stopped at dead centers at the same time, which would make it impossible to start the locomotive under its own steam.

[nanaimo73]

Has anyone read "Dropping the Fire" by C.P. Atkins ? Feltonhill said this book has a unbiased comparison of NYC's Niagara 4-8-4 and PRR's T1 4-4-4-4. What did this comparison say ?

Was the PRR really the only railroad that quartered with the other side ahead? Why was this ?

Did railroads order their coal in certain sizes, or did it not matter ? Did small pieces of coal drop through the grates and burn in the ashpan ? Did this cause problems ?

[M636C]

QUOTE: Originally posted by futuremodal

QUOTE: Originally posted by Old Timer

Murphy Siding - the four-wheel trailer was necessary to carry the weight of the larger firebox.

This brings to mind a question left unanswered on the T1 thread. Remember the 4-6-0 locomotives? They had a "gap" between the second and third set of drivers to support the firebox. I have assumed that since larger fireboxes required more width than could be afforded between 4' 8.5" gauge, they had to abandon the idea of supporting the firebox with the drivers and relegate that requirement to a supporting truck under the firebox. The question I had is this: Why couldn't the drivers support a wider firebox by extending outward the connecting rods between the driving axle in front of the firebox and the driving axle behind the firebox? That way you have more weight being supported by the drivers (e.g. more traction) instead of a non-driving trailing truck, while still maintaining the advantage of the larger firebox.

I assume that you are describing the "gap" between the drivers on turn of the (last) century 4-6-0 locomotives where the firebox (or possibly just the ashpan below the firebox) dropped down between the frames between the second and third axles. The later 1920s locomotives, like the Pennsylvania G5s had a gap despite the fact that they had a wide firebox above the driving wheels. The gap allowed the front of the firebox with its sloping grate to fit between the second and third axles. The G5s was as powerful as a Pacific type, but the firebox above the driving wheels limited the size of the driving wheels to 5'8" (if I remember correctly). The G5s was an excellent locomotive for commuter trains where the high adhesion from the firebox over the drivers allowed fast acceleration but the relatively small drivers were not a problem.

In the late 1930s a small number of oil burning 4-8-0s with wide fireboxes were built for the Nacional de Mexico. I believe these were the only modern 4-8-0s built in North America, and succeeded a number of Pacifics with similar boilers but larger wheels. The generally light track in Mexico took more kindly to these 4-8-0s than to larger and heavier 4-8-2s that would have been the conventional answer to the problem. I understand that these were a success, but were replaced by diesels after WWII.

The most extreme example of this concept was the British "Class 9F" 2-10-0 which despite the very restricted clearances in the UK, had a wide firebox boiler over 5' driving wheels, although the boiler was equivalent to that on a Pacific type with 6'2" drivers. This was the most powerful steam locomotive built in Britain and was intended for freight, but very early on, reports emerged of these locomotives running at 90 mph. One report appeared in a motor magazine in which, of all things, a Franco Crosti boiler version was photographed when last seen drawing away from a sports car (on road testing by the magazine) driving as fast as the road allowed. The last locomotive built of this type, No 92220 was painted green, and was occasionally used on express passenger trains, until the authorities indicated their displeasure. This indicated the flexibility of steam without a trailing truck at all.

With good balancing, a ten coupled locomotive could run fast, but it was only where weight and length restrictions were serious that a 2-10-0 would be better than a 2-10-4.

One of the objections to the fast running of the British 2-10-0s was that a single axle truck couldn't give sufficient guiding force for a large locomotive at high speed. The guiding force put higher flange load on a single axle truck than a two axle truck, which could distribute the forces between the axles. Another problem was the suspension of a single axle truck, which was usually a swing link system which could easily give uneven loads, usually lighter on the inside rail of the curve, and this could lead to derailments That is one reason that two axle lead trucks, usually with pre-compressed springs to allow side play at the pivot ,were preferred for high speed trains, and even for the Mexican 4-8-0s which were used in passenger service on lighter track.

M636C.

[GN-Rick]

Nanaimo, That is basically true. The only classes of modern steam
power on the GN without Belpaire fireboxes were the class P2 4-8-2s
and the S2 4-8-4s. (The Z6 Challengers don't count-they are not
representative of GN locomotives). Almost all other steam power no
the GN was Bepaire-equipped. The GN had the idea that the Belpaire
design was more efficient in heating (it was) and that design also
added more weight-which the GN liked on their freight locos-the
Belpaire design being heavier than an equivalent radial-stayed
boiler.

[nanaimo73]

Did GN have their steam engines built with Belpaires until they started getting diesels ?

[GN-Rick]

In fact, that's true, Murphy. The N3 turned out to be the tallest locomotive
on the GN, in part due to that very thing. Actually, I wasn't really advocating
the N3 as a response to futuremodal, I was simply submitting that loco
as a notable achievement by GN's shop forces. The two paragraphs don't
really dovetail that way. I was just expressing the opinion that longer-extended
rods would create a bad counterbalance problem and then a separate
opinion on the N3. It is intersting to note that GN got as much out of
the N3 as it did with that arrangement-of firebox built on top of the rear
drivers instead of a deep, truck-supported firebox as on most modern
steam locomotives of that time.

[Murphy Siding]

QUOTE: Originally posted by GN-Rick

A large problem with the concept of the 'extended rods' concept
would be a very serious increase in dynamic augment-the inertia
of extra mass reciprocating around the axles. It seems to me that
you would have a very rough-riding locomotive that would be almost
impossible to properly counterbalance-thereby increasing wear on
bearings and bushings. After all, counterbalancing even the locos
that existed was one of the more difficult tasks given to mechanical
departments and locomotive designers.

A notable steam loco, in my opinion is the class N3 2-8-8-0 as
rebuilt by the GN in 1940-42. An articulated loco with 63 inch
drivers, no trailing truck and only a two wheeled lead truck that
was capable of running with heavy loads at 50-60 mph. And with
an 118,000 lb tractive effort. Impressive-yet undernoticed.

Rick: If it is a 2-8-8-0 with no trailing truck, the firebox must be on top of the drivers? Wouldn't construction like that negate the need to do what futuremodal is asking?

[espeefoamer]

One very notable steamer was the SP cab forward,so designed to keep the engine crew from getting asphyxiated in the long tunnels on Donner pass.

[bobwilcox]

On the issue of how large fireboxes fit on locomoitves. Suggest you find a photo of a 19th century locomoitve (ie. 4-4-0) and see how the firebox fits between the drivers. Then get a look at a superpower locomotive with a four or six wheel trailing truck and see how the firebox is place up over the back drivers. This is particularly noticable on the UP's Big Boys. A picture is worth...

[GN-Rick]

A large problem with the concept of the 'extended rods' concept
would be a very serious increase in dynamic augment-the inertia
of extra mass reciprocating around the axles. It seems to me that
you would have a very rough-riding locomotive that would be almost
impossible to properly counterbalance-thereby increasing wear on
bearings and bushings. After all, counterbalancing even the locos
that existed was one of the more difficult tasks given to mechanical
departments and locomotive designers.

A notable steam loco, in my opinion is the class N3 2-8-8-0 as
rebuilt by the GN in 1940-42. An articulated loco with 63 inch
drivers, no trailing truck and only a two wheeled lead truck that
was capable of running with heavy loads at 50-60 mph. And with
an 118,000 lb tractive effort. Impressive-yet undernoticed.

[Anonymous]

QUOTE: Originally posted by Murphy Siding

I did a bunch of reading on this subject today. However I'm thinking that you're a little dimensionally challenged on this: The driver wheels are 4'-8" apart. The side rods are connected to the outter face of the drivers, at the outside radius. Height wise, the rods are a little taller off the ground than the drivers. No matter how you offset the connecting rods outward, the dimension between the drivers will remain about 4'-8".
The *old* steamers had the fire box between the drivers- therefore less than 4'-8" wide. The *newer* designs looked like the firebox was moved back, behind the drivers and no longer resrained to 4'-8" dimensional width. To carry the firebox weight, it looks like either 2 or 4 trailing wheels were added.

Murphy - Email your mailing address and I'll send you a drawing so you know what I'm talking about. It would be relatively easy to fit a 9' x 9' firebox in between a set of drivers which are 9.5' apart lengthwise and rods which are extended outward from the drivers at 9.5' apart widthwise.

Whether the weight of a larger firebox can be suspended between the two sets of driving wheels is another question altogether.

[mersenne6]

Well...probably the best known engine was the 4-4-0 American. The wheel arrangement and suspension were designed specifically for U.S. roads with their poor track and that particular wheel arrangement was the main type during the period when U.S. roads were being built at breakneck speed.

[Murphy Siding]

I did a bunch of reading on this subject today. However I'm thinking that you're a little dimensionally challenged on this: The driver wheels are 4'-8" apart. The side rods are connected to the outter face of the drivers, at the outside radius. Height wise, the rods are a little taller off the ground than the drivers. No matter how you offset the connecting rods outward, the dimension between the drivers will remain about 4'-8".
The *old* steamers had the fire box between the drivers- therefore less than 4'-8" wide. The *newer* designs looked like the firebox was moved back, behind the drivers and no longer resrained to 4'-8" dimensional width. To carry the firebox weight, it looks like either 2 or 4 trailing wheels were added.

[Anonymous]

QUOTE: Originally posted by Murphy Siding

QUOTE: Originally posted by futuremodal

The side rods are(were) connected on the outside and next to the driving wheels (which are 4' 8 1/2" apart widthwise, give or take material dimensions), so the rods on opposite sides of each other are(were) about 5 - 5 1/2'(?) apart in width. The larger fireboxes were made to maximize the allowable width of a locomotive 10', maybe 10 1/2' wide. So you couldn't have the typical side rods compatable with the wider fireboxes as was done with the 4-6-0 locomotives. But if you could somehow extend outward the connection between the rod and driver wheel by a foot or so, you could conceivably fit a firebox with a 9' or so width between such outwardly extended rods between a front set of drivers and a rear set, and support this firebox between such driver wheels. I do not know if this is technecally feasable, but I see no reason why it wouldn't work as intended.

My guess is that you'd be making the engine wider-maybe too wide for some clearance situations like tunnels?

You would keep it all within the specified dimensions.

[Anonymous]

Regarding stories from engineers who drove steam engines.. I am concerned that there may not be many left alive to tell us what they were doing in that era.

I dont have much to offer except what I have learned on trips to tourist steam such as EBT, Strasburg and Cass etc... On strasburg there was a 4-4-0 that used to provide service until it's firebox was deemed unsafe. It was a favorite because it ran really well. I suppose it was "Talky" thru the stack as it hauled the train up and down the gentle hills; compared to the larger engines that did not have much talk in the stack.

If I was to listen to a recording of the EBT's #17 whistle and all I probably can pick it out right away. We would listen for it as we waited at the depot for the next train. That long single blast while it was just coming into view preparing to stop had the people running about getting the children ready.

There was a recording of the Southern's 4-6-2 Cresent Limited I recall as it tried to climb a mountain range (Front royal?) it was a machine under great load and you could almost "See" the crew working to keep that train moving up hill as the steam worked. That must have been a sight for those lucky enough to see it.

Finally books have pictures with captions saying "Engineer closed the smoke as they passed someone's laundry near the tracks" Apparently it was a story of people trying to be good neighbors by not dirtying up someone's wa***hat was on clotheslines drying as the train passed. (Usually white sheets =)

[Murphy Siding]

QUOTE: Originally posted by futuremodal

The side rods are(were) connected on the outside and next to the driving wheels (which are 4' 8 1/2" apart widthwise, give or take material dimensions), so the rods on opposite sides of each other are(were) about 5 - 5 1/2'(?) apart in width. The larger fireboxes were made to maximize the allowable width of a locomotive 10', maybe 10 1/2' wide. So you couldn't have the typical side rods compatable with the wider fireboxes as was done with the 4-6-0 locomotives. But if you could somehow extend outward the connection between the rod and driver wheel by a foot or so, you could conceivably fit a firebox with a 9' or so width between such outwardly extended rods between a front set of drivers and a rear set, and support this firebox between such driver wheels. I do not know if this is technecally feasable, but I see no reason why it wouldn't work as intended.

My guess is that you'd be making the engine wider-maybe too wide for some clearance situations like tunnels?

[Anonymous]

The side rods are(were) connected on the outside and next to the driving wheels (which are 4' 8 1/2" apart widthwise, give or take material dimensions), so the rods on opposite sides of each other are(were) about 5 - 5 1/2'(?) apart in width. The larger fireboxes were made to maximize the allowable width of a locomotive 10', maybe 10 1/2' wide. So you couldn't have the typical side rods compatable with the wider fireboxes as was done with the 4-6-0 locomotives. But if you could somehow extend outward the connection between the rod and driver wheel by a foot or so, you could conceivably fit a firebox with a 9' or so width between such outwardly extended rods between a front set of drivers and a rear set, and support this firebox between such driver wheels. I do not know if this is technecally feasable, but I see no reason why it wouldn't work as intended.

[Murphy Siding]

QUOTE: Originally posted by futuremodal

QUOTE: Originally posted by Old Timer

Murphy Siding - the four-wheel trailer was necessary to carry the weight of the larger firebox.

This brings to mind a question left unanswered on the T1 thread. Remember the 4-6-0 locomotives? They had a "gap" between the second and third set of drivers to support the firebox. I have assumed that since larger fireboxes required more width than could be afforded between 4' 8.5" gauge, they had to abandon the idea of supporting the firebox with the drivers and relegate that requirement to a supporting truck under the firebox. The question I had is this: Why couldn't the drivers support a wider firebox by extending outward the connecting rods between the driving axle in front of the firebox and the driving axle behind the firebox? That way you have more weight being supported by the drivers (e.g. more traction) instead of a non-driving trailing truck, while still maintaining the advantage of the larger firebox.

I don't understand the question.[%-)]. Please explain extending outward the connecting rods........ Thanks

[Anonymous]

QUOTE: Originally posted by Old Timer

Murphy Siding - the four-wheel trailer was necessary to carry the weight of the larger firebox.

This brings to mind a question left unanswered on the T1 thread. Remember the 4-6-0 locomotives? They had a "gap" between the second and third set of drivers to support the firebox. I have assumed that since larger fireboxes required more width than could be afforded between 4' 8.5" gauge, they had to abandon the idea of supporting the firebox with the drivers and relegate that requirement to a supporting truck under the firebox. The question I had is this: Why couldn't the drivers support a wider firebox by extending outward the connecting rods between the driving axle in front of the firebox and the driving axle behind the firebox? That way you have more weight being supported by the drivers (e.g. more traction) instead of a non-driving trailing truck, while still maintaining the advantage of the larger firebox.

[Murphy Siding]

QUOTE: Originally posted by Wdlgln005

You may be starting a bit of a flame war between similar locos on different railroads. No 2 steamers were exactly the same, unlike diesels. some versions could be good steamers, others unlucky or junk. Since they were custom built, a lot depends on the operating character of each RR. It becomes fun to try to compare J class Northerns on N&W with those on UP or any other RR.

The 4 wheel pilot truck was developed fairly early for the steamer to be guided over poorly built track. 2 wheel trucks were used for slow moving freight. Driving wheel diamaters determined speed. Large 60" drivers could easily move the engine at 60 per hour, Smaller ones gave more traction & HP or drawbar pull. Adhesion is the factor that determines how much HP is available to pull a train.

The class number like J, depends on the railroad. Some roads gave the little teakettles A's, the next one B's etc. A J3 would be the third group of locos purchased. Chances are, lessons learned will result in improved locomotives with different valve gear, stokers, & other changes. You would get a huge argument over who had the best Northerns. In the South, they would be called Dixies or Yellowjackets. The Yellowjacket name comes from the yellow painted stripe on the running board edge & tender of locos.

The best stories should come from the engineers that operated & controlled all this machinery. No computers. Not many automatic appliances. Hot in the summer. Cold in the winter, except for the heat provided from the firebox. Yet, the enginemen operated these machines for over a century in all kinds of conditions. Crews on the FEC tried to outrun the hurricane that destroyed the RR. Today, Amtrak was unable to run trains near the zone till the storm passed.

Flame Wars![:0] That's certainly not the intention. I read a lot of racing forums, where very few topics get much further than "My driver rocks-your driver sucks".[V] My interest lies in all the reading I do. Every railroad book with some history in it (and which one wouldn't have some history?) will feature the steamer that a particular railroad is known for. I could care less for the arguements of which is better?- a Texan or a Selkirk?
So many European history books I read have frequent phrases and references in French. [sigh] I don't speak French. It can get so annoying! It's easy for me to comprehend an RS-3 or a GP-7. Unfortunatelly , I'll read something like "The railroad's fortunes reversed when they traded their Mikados for Hudsons". [?] I don't speak French! Since there are so many people on here with vast knowledge of steamers, could you share?

( Yes, I know-your driver rocks-mine sucks, so can we please get far past that allready?)
Thanks

[Murphy Siding]

QUOTE: Originally posted by Lotus098

Get your self a good book like mine. "The Steam Locomotive A Century of North American Classics" by Jim Boyd. If this doesn't get you interested in steam, nothing will.

I have that book. Went and got it out to re-read. Anything by Jim Boyd is excellent.[:)]

[Wdlgln005]

You may be starting a bit of a flame war between similar locos on different railroads. No 2 steamers were exactly the same, unlike diesels. some versions could be good steamers, others unlucky or junk. Since they were custom built, a lot depends on the operating character of each RR. It becomes fun to try to compare J class Northerns on N&W with those on UP or any other RR.

The 4 wheel pilot truck was developed fairly early for the steamer to be guided over poorly built track. 2 wheel trucks were used for slow moving freight. Driving wheel diamaters determined speed. Large 60" drivers could easily move the engine at 60 per hour, Smaller ones gave more traction & HP or drawbar pull. Adhesion is the factor that determines how much HP is available to pull a train.

The class number like J, depends on the railroad. Some roads gave the little teakettles A's, the next one B's etc. A J3 would be the third group of locos purchased. Chances are, lessons learned will result in improved locomotives with different valve gear, stokers, & other changes. You would get a huge argument over who had the best Northerns. In the South, they would be called Dixies or Yellowjackets. The Yellowjacket name comes from the yellow painted stripe on the running board edge & tender of locos.

The best stories should come from the engineers that operated & controlled all this machinery. No computers. Not many automatic appliances. Hot in the summer. Cold in the winter, except for the heat provided from the firebox. Yet, the enginemen operated these machines for over a century in all kinds of conditions. Crews on the FEC tried to outrun the hurricane that destroyed the RR. Today, Amtrak was unable to run trains near the zone till the storm passed.

[nanaimo73]

Murphy,
Thank you for starting a steam thread.

I think this is the best thread on the forums:
www.trains.com/community/forum/topic.asp?TOPIC_ID=31139

[selector]

It only had two. Thus, the designation of 2-8-4. The Mountain class were 4-8-2's. Other engines with four wheels in the lead truck were the 4-4-0 (American), the 4-6-2 (Pacific), and the 4-8-4 (Northern). Then, in the big stuff, they had the 4-6-6-4's, and so on.

Although I cannot claim to know it for certain, I suspect that two axles were needed on the front for the same reason as they were needed for the firebox; to support weight. in the case of leading trucks, they also were meant to horse the loco's nose around curves at speed, so they needed mass.